Biology

6. The transverse section of a plant material shows the following anatomical features – (a) the vascular bundles are conjoint, scattered and surrounded by a sclerenchymatous bundle sheaths. (b) phloem parenchyma is absent. What will you identify it as?

Solution: Monocot stem is used for the traversing section. Because the vascular bundles in monocot stems are distributed, this is the case. There is no phloem parenchyma to be identified.

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Fill in the gaps:
(a) Ascending limb of Henle’s loop is ______ to water whereas the descending limb is _______ to it.

(b) Reabsorption of water from distal parts of the tubules is facilitated by hormone _______.

(c) Dialysis fluid contain all the constituents as in plasma except _______.

(d) A healthy adult human excretes (on an average) _______ gm of urea/day

Let's take a look at each assertion separately.(a) Water is impermeable to the ascending limb of Henle's loop but permeable to the descending limb.An ascending limb, a descending limb, and a hairpin...

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Name the following:
(a) A chordate animal having flame cells as excretory structures

(b) Cortical portions projecting between the medullary pyramids in the human kidney

(c) A loop of capillary running parallel to the Henle’s loop.

Solution: The following are the one word answers- Amphioxus is a chordate animal with flame cells as excretory organs. Some animals have excretory structures called flame cells or...

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Indicate whether the following statements are true or false:
(a) Micturition is carried out by a reflex.

(b) ADH helps in water elimination, making the urine hypotonic.

(c) Protein-free fluid is filtered from blood plasma into the Bowman’s capsule.

(d) Henle’s loop plays an important role in concentrating the urine.

(e) Glucose is actively reabsorbed in the proximal convoluted tubule.

Solution: The following statements are explained as- (a) Micturition is a reflex reaction of passing urine. The stretch receptors in the bladder wall are stimulated by distension, and reflex action...

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Name the stage of cell cycle at which one of the following events occur:
(i) Chromosomes are moved to spindle equator.

(ii) Centromere splits and chromatids separate.

(iii) Pairing between homologous chromosomes takes place.

(iv) Crossing over between homologous chromosomes takes place.

Solution: (i)In Metaphase, chromosomes are transported to the spindle equator. ii) In Anaphase, centrosomes split and chromatids separate. iii) In meiosis, the pairing of homologous chromosomes...

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Differentiate between the following:
(a) Diffusion and Osmosis

(b) Transpiration and Evaporation

(c) Osmotic Pressure and Osmotic Potential

(d) Imbibition and Diffusion

(e) Apoplast and Symplast pathways of movement of water in plants

(f) Guttation and Transpiration

Solution: The diffusion between all the following sets are- a) Diffusion and Osmosis DiffusionOsmosisIt is a form of passive transport in which a chemical moves from an area of higher concentration...

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Which of the following statements are true? If false, correct them:
(a) Boron deficiency leads to stout axis.

(b) Every mineral element that is present in a cell is needed by the cell.

(c) Nitrogen as a nutrient element is highly immobile in the plants.

(d) It is very easy to establish the essentiality of micronutrients because they are required only in trace quantities.

Solution: a) True b) False: Every mineral element found in a cell is not required by the cell. c) False- Nitrogen is a very mobile nutrient in plants. d) False- Since micronutrients are only...

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